In a large saucepan or Dutch oven, heat 2 tablespoons of olive oil over medium-low heat. Add 1 finely chopped shallot, 3 minced garlic cloves, and 1 diced celery stalk. Sauté for about 5 minutes, stirring occasionally until the shallots become translucent and fragrant.

Stir in 2 cups of diced pumpkin and cook for an additional 5 minutes, stirring frequently. Add 1 chopped fennel bulb and continue to cook for another 3 minutes.

Increase the heat to high and add 1 pound of ground beef, breaking it up with a wooden spoon as it cooks. Brown the meat for about 10 minutes, stirring occasionally until it's fully cooked.

Mix in 1 teaspoon of dried thyme, 1 teaspoon of sage, 1 teaspoon of marjoram, and ½ teaspoon of chili flakes, along with salt and pepper. Stir the spices into the meat and let them infuse flavors for 1-2 minutes.

Pour in 1 cup of beef broth and toss in a bay leaf. Bring the mixture to a gentle simmer and let it cook for about 10 minutes.

Add 1 can (28 ounces) of puréed tomatoes and 2 tablespoons of tomato paste to the meat mixture. Stir well, cover, and allow it to simmer for another 10 minutes.

While your Pumpkin Beef Bolognese simmers, bring a large pot of salted water to a boil. Cook your preferred pasta according to the package instructions until al dente.

Plate the cooked pasta, generously topping it with the warm Pumpkin Beef Bolognese sauce. Optionally, add a dollop of whipped ricotta for a creamy finish.